dlatzm.f man page

dlatzm.f —

Synopsis

Functions/Subroutines

subroutine dlatzm (SIDE, M, N, V, INCV, TAU, C1, C2, LDC, WORK)
DLATZM

Function/Subroutine Documentation

subroutine dlatzm (characterSIDE, integerM, integerN, double precision, dimension( * )V, integerINCV, double precisionTAU, double precision, dimension( ldc, * )C1, double precision, dimension( ldc, * )C2, integerLDC, double precision, dimension( * )WORK)

DLATZM

Purpose:

This routine is deprecated and has been replaced by routine DORMRZ.

DLATZM applies a Householder matrix generated by DTZRQF to a matrix.

Let P = I - tau*u*u**T,   u = ( 1 ),
                              ( v )
where v is an (m-1) vector if SIDE = 'L', or a (n-1) vector if
SIDE = 'R'.

If SIDE equals 'L', let
       C = [ C1 ] 1
           [ C2 ] m-1
             n
Then C is overwritten by P*C.

If SIDE equals 'R', let
       C = [ C1, C2 ] m
              1  n-1
Then C is overwritten by C*P.

Parameters:

SIDE

SIDE is CHARACTER*1
= 'L': form P * C
= 'R': form C * P

M

M is INTEGER
The number of rows of the matrix C.

N

N is INTEGER
The number of columns of the matrix C.

V

V is DOUBLE PRECISION array, dimension
        (1 + (M-1)*abs(INCV)) if SIDE = 'L'
        (1 + (N-1)*abs(INCV)) if SIDE = 'R'
The vector v in the representation of P. V is not used
if TAU = 0.

INCV

INCV is INTEGER
The increment between elements of v. INCV <> 0

TAU

TAU is DOUBLE PRECISION
The value tau in the representation of P.

C1

C1 is DOUBLE PRECISION array, dimension
               (LDC,N) if SIDE = 'L'
               (M,1)   if SIDE = 'R'
On entry, the n-vector C1 if SIDE = 'L', or the m-vector C1
if SIDE = 'R'.

On exit, the first row of P*C if SIDE = 'L', or the first
column of C*P if SIDE = 'R'.

C2

C2 is DOUBLE PRECISION array, dimension
               (LDC, N)   if SIDE = 'L'
               (LDC, N-1) if SIDE = 'R'
On entry, the (m - 1) x n matrix C2 if SIDE = 'L', or the
m x (n - 1) matrix C2 if SIDE = 'R'.

On exit, rows 2:m of P*C if SIDE = 'L', or columns 2:m of C*P
if SIDE = 'R'.

LDC

LDC is INTEGER
The leading dimension of the arrays C1 and C2. LDC >= (1,M).

WORK

WORK is DOUBLE PRECISION array, dimension
            (N) if SIDE = 'L'
            (M) if SIDE = 'R'

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 152 of file dlatzm.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

dlatzm(3) is an alias of dlatzm.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK